Locking arrangement with burglar alarm

Abstract

A cylinder lock is provided with a contact carrier for the movable contact of a switch in an electrically operated burglar alarm. A spring mounted on the contact carrier and radially projecting from the casing of the lock is stressed by engagement with the wall of the door aperture receiving the lock and biases the contact carrier toward a switch opening position. When it is attempted to pull the lock from the door, the spring pivots the contact carrier and the alarm is energized.

What is claimed is: 
     
       1. A locking arrangement comprising: a. a casing element defining an axis of rotation;   b. a cylinder element mounted in said casing element for angular movement about said axis and formed with a key slot extending inward of one axially terminal face of said cylinder element;   c. tumbler means in said elements for normally preventing said angular movement and responsive to a key inserted in said key slot for permitting said movement;   d. a spring member having a portion radially projecting from said casing element, said portion being axially movable relative to said casing element, said spring member being stressed resiliently when said portion is moved in one axial direction;   e. first and second contact means mounted on said casing element in electrically insulated relationship; and   f. motion transmitting means interposed between said spring member and said first contact means for biasing said first contact means toward a circuit opening position remote from said second contact means in response to said stressing of said spring member, and for conductively engaging said first and second contact means in response to movement of said portion in the other axial direction.   
     
     
       2. An arrangement as set forth in claim 1, further comprising a driver member mounted on said cylinder element for joint angular movement and projecting from the other axially terminal face of said cylinder element, and turn means engaged by said driver member, said turn means including a housing and a latch member mounted on said housing for reciprocating movement in response to said joint angular movement, said motion transmitting means including a contact carrier movably mounted on said casing element and carrying said first contact means. 
     
     
       3. An arrangement as set forth in claim 2, wherein said spring member is elongated, said portion thereof is a free longitudinal end portion, and said spring member is flexed when said end portion moves in said one axial direction. 
     
     
       4. An arrangement as set forth in claim 3, further comprising pivot means securing said contact carrier to said casing for angular movement in a plane substantially parallel to said axis. 
     
     
       5. An arrangement as set forth in claim 2, further comprising first fastening means for fastening said casing element in an aperture of a plate-shaped body in a position in which said portion of said spring member engages said body in said aperture, second fastening means for mounting said turn means on said body for pivotal movement relative to said body, third contact means mounted on said latch means for movement therewith, fourth contact means, and third fastening means for fastening said fourth contact means on said body in a position for engagement by said third contact means during said pivotal movement of said turn means. 
     
     
       6. An arrangement as set forth in claim 5, further comprising abutment means engageable with said turn means for limiting said pivotal movement, and yieldably resilient means biasing said turn means toward engagement with said abutment means. 
     
     
       7. An arrangement as set forth in claim 1, wherein said tumbler means include a pair of tumbler pins radially aligned in respective bores of said elements in a predetermined angular relationship of said elements for joint, radial movement inward and outward of said key slot, and third contact means operatively connected to one of said tumbler pins for conductively engaging said one contact means in response to radially outward movement of said one tumbler pin. 
     
     
       8. An arrangement as set forth in claim 1, further comprising fastening means for fastening said casing element in an aperture of a plate-shaped body in a position in which said portion of said spring member frictionally engages said body in said aperture, said fastening means including yieldably resilient means opposing axial movement of said casing element in said aperture. 
     
     
       9. An arrangement as set forth in claim 8, wherein said fastening means include a mounting member, means for fixedly fastening said mounting member to said body, a pressure plate fixedly fastened to said casing element, and a spring axially interposed between said mounting member and said pressure plate. 
     
     
       10. An arrangement as set forth in claim 9, wherein said mounting member is approximately cup-shaped and defines a cavity receiving said pressure plate and said spring. 
     
     
       11. An arrangement as set forth in claim 1, further comprising a sleeve member formed with a passage therethrough dimensioned to receive said casing element therein, and engaging means on said sleeve member in said passage for engaging said portion of said spring member, and for impeding axial movement of the engaged portion when said casing element is received in said passage.